Discharge tube



Feb. 12,1932. MEYER ET AL 1,843,645

DISCHARGE TUBE Original Filed Dec. 19. 1927 INVENTORS FR/Ea/P/U/ ME 75/? HANS J SPAN/V5)? Patented F ch. 2, 1932 rnmnmcnfl MEYER Aim HANS ,,.ioAcnii r SPANNER, on IIIBERLIN,'GERMA1TY, 'AIIID EDMUND GERMER, OF STOCKHOLM, SWEDEN, ASSIGNORS, BY MESNE ASSIGNMENTS,

To miic'rnons, 1am, A CORPORATION or DELAWARE DISCHARGE TUBE ori ii ai applicationflled December is, 1927, Serial no. 241,035, and in Germany-December 10. was. 1 Divided and this application filed February 9, '1928. Serial no. 253.040,

The present invention relates to discharge tubes, such as, colored glow tubes for advertisingpurposes, ultra violet ray tubes, and the like, and. more, particularly to means 5 facilitating the starting of, such tubes into operation without using potentials higher than those available for 'the general operation of such tubes. Y

' In our copending applications Serial Numbers' 241,034 and 241,035, filed December 19,

1927, we describe and claim the construction and arrangement of such tubes permitting operation of them directly from low potential commercial lighting and power systems, such as 110 and 220 volt systems, including in particular arrangements permitting satisfactory operation with alternating current "at such low potentials. We provided electron emitting electrodesalternately acting as cathodes and anodes to reduce by reason of electron emission the so-called cathode fall or drop of potential, describing both sepa-- rately heated ele ttron emitting cathodes and.

cathodes deriving electron emitting heating i from the ionic bombardment taking place after the discharge has been started. 'In the case of the latter type of cathode we provid- -ed auxiliary electrodes in close proximity as starting electrodes, this because the tube must be started cold and without any way of bringing on electron emission until ionic bombardment is had.

This application is a division of our-copending application Serial Number 241,035,

filed December 19, 1927, and relates -particu .larly to the elimination of the difficulty had in starting a gas filledtube having a plural- "ity of-incandescent electrodes, a reason different from that which has long prompted the use of starting devices with initially cold cathodes, so that without special provision a starting potential considerably higher than that required for continued operation after the discharge has been created may be required for the separately heated type of cathode. This condition arises from the initially -hot-' cathode creating about itself a field' or cloud of electrons which, though later are most'desirable, act to prevent the" commencement of, ionization by being sufiicient in number to neutralize ions'as fast as created. Once the discharge is develo ed the ions predominate, and the electron eld is thereafter incapable of subduing the ionization. v

We-have found that a positively charged body or'auxiliary electrode in the neighborhood of the electron emitting cathode so dispenses the electron cloud while the main discharge potential is producing a sufficiently intensive ionization to overcome the entire electron field if later releasedfroi'n the infl ience of the auxiliary charged body that starting ofthe main discharge can be readily had. with any excess potential.

The one figure of the drawings illustrates the manner in which the desired result is accomplished. The tube VT includes a gas,

filling of desired character and pressure to .produce the glow discharge or other result It includes electrodes desired of the tube. F and F mounted in suitable stems S and S in the two ends, having suitable lead-in Wires all common in practice. The electrodes F and F are coated with suitable electron emitting compounds capable of withstanding considerable ionic bombardment, and

must be so capable because they alternately act ascat-hodes and anodes when alternating current is used. These electrodes are heated for electron emission by current. passing th-roiz hthem derived-from secondary windingsb and S of suitable potentials of the alternating current transformer illustrated.

The two electrodes have impressed across them the full line potential, as can be seen from tracing the leads L L connected at opposite ends of primary to the center tap connections in secondariess S connected to the electrodes.

The auxiliary electrodes A and A are placed close to electrodes F and F respectively, and have in series with their external leads resistances R and-R When circuit breakers B and B are down, as they are before the main discharge commences, it will be seen that the line potential is across each main electrode and its corresponding auxiliary electrode, and" if any discharge takes place between these electrodes it is limited by the series resistance to any degree desired by choice of value of this resistance. As soon as the main discharge takes place largecurrent flowsthrough the pick-up coils'of circuit breakers B and B to open the auxiliary circuits, thus'preventing waste of current after the auxiliary system has served its purpose; though the circuit breakers may be omitted and resistances R and R made so large as to keep the-auxiliary current sufficiently low to keep the waste current reasonably low.

1. In a glow lamp system including .an envelope having-a gas therein, a plurality of incandescent electrodes spaced apart therein and auxiliary electrodes inclose proximity to eachof said incandescent electrodes, the combination of a transformer having a 1 primary and a plurality of secondaries corresponding in number to said incandescent electrodes, connections between each secondary and its corresponding electrode, connec-' tions between each secondary and each terminal of said primary, anda connection between each terminal of said primary and the auxiliary electrode adjacent the incandescent electrode electrically connected to the other terminal of said primary whereby the electron field around the incandescent electrode acting as an anode is dispersed and ionization of the gas surrounding said electrode is developed.

' 2. In a glow lamp system including an envelope having gas. therein, a plurality v of incandescent electrodes spaced apart therein and auxiliary electrodes in "close proximity to each of said incandescent electrodes, the combination of a transformer having a primary and a plurality of secondaries corresponding in number to said incandescent electrodes, connections between each secondary and its corresponding electrode,

connections between each secondary and each aeeaeea.

envelope having a gas therein, a plurality of electrodes, connections between each secondary and its corresponding electrode, connections between each secondary and each terminal of said primary, circuit breakers, the coil of each of which is contained in one of said last namedv connections, and a connec-- tion between each terminal of said primary and the auxiliary electrode adjacent the candescent electrode electricallyconnecte'dto the other terminal of said primary, said connections cgntaining the. contacts. of said circuit breakers whereby the electron field around the incandescent electrode acting as an anode is glispersed and ionization of the gas surrounding said electrode is developed. Having described our mvention we claim:

incandescent electrodes spaced apart there- 4. Ina glow lamp system, the combination of an envelope having-a gas therein, a plurality of incandescent electrodes spaced apart therein, a corresponding number of auxiliary electrodes each in close proximity" vto said incandescent electrodes and means for maintaining the'auxiliary electrode of one incandescent electrode at a definite potential relative to the potential of another of said incandescent "electrodes, means between said auxiliary electrode and said mainelectrode for maintaining the value of curoperating condition, and means for disconnectmg said auxiliary electrodes when cur- 1 rent flows between said incandescent electrodes, said means consisting of a plurality of circuit breakers, the coils of which are contained in the circuits between the main electrodes and the contacts of which are includedin' the circuits of said auxiliary electrodes.

FRIEDRICH MEYER. r

grrans aoaonm SPANNER. j n

EDMUND terminal of said primary, each connection containing an impedance of predetermined value, and a connectionbetween each terminalof said primary an'dfthe auxiliary electrode adjacent the incandescent electrode electrically connected to the other terminal, or said primary whereby the electron field around the incandescent electrode acting as an anode is dispersed and ionization of the 65, gas surrounding said electrode is developed.

3. iln a glow lamp system including an cenrmem: or coknncrion.

Patent No. 1, 843, 645. Granted February 2, 1932, to I FRIEDRICH Miami ET r;

, It is hereby certified that error appears in'the printed specification of the above numbered patent'reqnirin'g correction as follows: Page I,' "line 38, strike out the comma and words a reason" and insert instead: periodand the words This difficulty is; lines 58 and 59, for' "dispenses" read disperses; and line 65, for "with" read withoht; and that the said Letters Patentshould be read with these correctionstherein that the same may conform to the record of thccase in the Patent Office. e

Signed and sealed this22nd day of March, A. D. 1932;

M. J. Moore;

(Seal) I ,A c ting conmissioner of Patents. 

